Compass mounting



March 19, 1935.

L. DE FLOREZ COMPASS MOUNTING Filed Sept. 1, 1933 Zu/s DEFLoREZ INVENTOR Patented Mar. '19, 1935 I 1,994

UNI TE o STATES PATENT ,OFFlC-E Luis de Flores, New York, N. Y. Application September 1, 1933, Serial No. 687,738

e 11 (CL 248-40) The general purpose of this invention is to protype involvingfa sensitive, lightly balanced magvide a mounting for precision instruinentsand netic needle 5 mounted in a case 6 closed by delicate mechanisms which will protect them transparent cover 7 and cooperating with a spefrom vibration causing deterioration and errors cial compass dial later ,described.

,5 in reading and which at the same time will hold Surrounding the case of the instrument is a 6 them in position with sufiicient firmness to incup shaped housing 8 and connecting the two is sure accurate operation. a flexible resilientmetallic bellows 9, frequently Instrumentsmounted in airci'aft, fastmotor termed a sy P boats and the like are subject to sharp and vary- In the first form of the invention shown, the

ing vibratory motions in addition to .varying sylphon supports the compass in tension; where- 10 forces exerted by the motion of the craft itself. as in the second form shown, the bellows sup- Various attempts have been made to overcome P rts the compass instrument in compression.- the undesirable and harmful effects produced Accordingly in Figure B-the bellows is shown by these disturbing forces, involving usually the suspended in theecasing by a mounting ring 10 mounting of such instruments on felt, rubber secured to the upper flanged end 11 of the bel- 15 or other soft and elastic materials. Such mountlows and held by the screws 12 to the under side tings however are only moderately effective in-.- of the inturned flange 13- at the upper end of. the volving as they do a certain degree of looseness casing. The case of the'instrument is shown sepermitting undesirable freedom of movement recured by. screws 14 in supported relation on a 20. sulting in inaccuracies in reading and also bering '15, secured to the lower flanged end 16 of 2 cause at certain -speeds the-periods of vibration the bellows. are such as to cause certain delicate instru By the construction described the bellows is ments, such as a compass to hunt or swing sealed in the mounting cup so that fluid within through a wide arc and under some severe conthe space 17 confined between the two may serve ditions actually to completely revolve. as a damping agent to control vibrations and os- 25 It has been found as a result of considerable cillations of the sylphon and supported instruresearch that such vibrations can be overcome -ment. This damping fluid may simplybethe c'oneffectively by certain damping mechanism perfined'air or'other medium may be provided. 'mitting of limited vertical, lateral and rocking In addition to or in place of the fluid damping 80 movements. 1 medium, mechanic damping medium may be '40 on low pivot friction.

For purposes of disclosure, the invention is provided, such as a layer or'layers 1B of felt-or .-shown as applied to a compass, which thus prolike resilient material, confined in the casing tected against vibration and consequent pivot jar-.- about the sylphon and in contact with the outer ring is made extremely sensitive, quick and folds of thesame. 3Q smooth in action. In such connection the inven- Instead of the suspension mounting described, tion is a material aid to navigation, particularly the compression support illustrated in Figure 4 in aircraft where. swinging. vof the compass may be used, the main distinction in this illustracard or needle is a serious diillculty and where' tion being-that in such case thering 19 attached toefi'ectiveness of the compass is largely dependent. the lower end'of the bellows may rest on the bottomof the cup'shaped housing, secured as by 40 'In the drawing, forming part of the specifi-- screws 20, and that the compass may have a cation, there. are illustrated different embodir flange or lugs 21 seated-on the upper bellows ring ments of the invention and it is to be under- 22, secured by screws 23'. Ifthe mounting lugs stood that the, structure may be further varied, 21 be extended as a continuous flange, there will all withinthe true intent and broad scopeof the then be a damping chamber 24 completely eninvention hereinafter defined. closed between the compass case and housing cup, Figures 1 and 2 are plan views of one embodiof substantially the same effect as the damping ment of the invention the mounting trunnions chamber 17 in the first-form described. 'With being shown as broken away. I separated lugs, however, as disclosed, the pump- Figure 3 is a broken and vertical cross secing action froni'moveme'nt of the sylphon will be 50 tional view of the structure. less effective for damping purposes. The amount a Figure 4 is a generally similar broken and verand extent or reliefopenings, such as those shown tical sectional view illustrating another embodibetween the mounting lugs, may be governed to ment of the invention a I regulate the displacement action and hence the n The compass illustrated is ofcjthc aperiodic desired amount of fluid damping.

Where there is less or practically no fluid damping,asmaybethecaseasshowninFlgure4, mechanical damping may be employed after the manner shown in Figure 3, or as indicated in the Figure 4 construction, by placing washer-like layers 35, 26 between either or both the outer folds and the inner folds of the bellows structure.

The housing shown in Figure 4 is of true cup formation, with a solid or integral back; whereas,

in the first design shown, the housing has a re-- movable back wall 27 secured by screws 28, both forms having special advantages.

The broken lines at 28 in Figures 3 and 4 show how a compensator for the compass may be conveniently mounted on the back wall of the housing. Also, in the several views, trunnions are indicated at 30, directly attached to the housing by which the unit structure may be tiltably mounted for leveling purposes.

It will be apparent that the invention provides a universal cushion mounting for a compass or like sensitive instrument, which allows relatively free movement vertically, horizontally and laterally and without permitting twisting on the verti- 'cal axis of the ship. The compass, in the case of aircraft use, is thus cushioned against vibrations and held fixed on the line of flight or axis,

of the ship while free to rock or oscillate as required to absorb vibrations or accommodate itself to movements of the'ship. Natural periods of vibration may be predetermined and controlled by resiliency size and number of folds of the sylphon and weight of the superimposed load and suitable damping may be employed by utilizing the displacement action of the sylphon and damping medium, such as felt or like, disclosed. The cushioning effect is determined by the resiliency of the bellows and the damping control exercised thereon. One or more small openings 41 may be provided in the back of the case for relief of air and release of condensed moisture. The damping eifect may be relatively slight, permitting, particularly if a long bellows is employed, an actual lateral shifting of the supported instrument. This may permit the compass to shift laterally to one side of the axial line of the craft, but in-such event it will still remain parallel with the true axis and therefore accurate for navigation of the ship. This motion is very valuable to :ibsorb'certain undesirable components of vibra- I The bellows is a simple mechanical structure" and while desirably resilient, is relatively rugged and accurate in the sense of being equally yieldable in all directions, that is, withthe exception ".flange and held by thumb screw 37.

Knobs 38 are shown on the compass card, by which it. may be turned to bring the north and south indications thereon in line with the needle. The parallel lines 39 cross this card, assisting such adjustment. The vernier plate is shown as hav- 'ing a scale of live degree marks of! to the left of the index point 40 thereon, to be used in conjunction with and in addition to the ten degreemarkings on the compass card.

The rotatable compass card. can be quickly turned and secured in the angular position of degrees left of north for the direction of travel and thereafter the pilot merely needs to hold the ship with the arrow pointing north on the shifted compass scale. The parallel lines 39 on the compass card aid in this, in that they should be kept parallel with the needle, being easy to read with the instrument set as usual, at a position in front of the pilot. The forty-five degree pointers 33 on the compass needle also are of aid in holding the course since one or more of them may usually be alined with a point on the compass scale from 'the pilot's position at the controls.

This new compass structure enables closer and more accurate navigation and the universally resilient mounting of the same cushions and maintains this sensitive, easily read compass always in true indicating relation. One particular objection overcome by the invention is the swinging action of the needle, occasioned by the compound vibrations existing at times in airplanes, the universal spring mounting absorbing or counteracting th e vibrations suiiiciently to maintain the needle 5 eady and the instrument accurate and reliable under all such conditions.

What is claimed is:

1. In combination, a compass or like sensitive instrument and a cushion support for the same, comprising a resilient metallic bellows surrounding and enclosing said .compass or like instrument, means securing one end of said bellows structure in supporting connection with the comnected with the opposite end portion of said me-- tallic bellows structure, the bellows structure being supported at the lower end of the same and the compass or like instrument being supported on the upper end of the bellows structure.

3. In combination, a compass or like sensitive instrument and a cushion support for the same, comprising an expansible and contractible resilient bellows structure connected at one end with said instrument, supporting means connected with the opposite end portion of said bellows structure and annular resilient damping material engaging loops of the folds in said bellows structure.

4. In combination, a compassor like sensitive instrument and a cushion support for the same, comprising an expansible and contractible resilient bellows structure connected atone end with said instrument, supporting means connected with the opposite end portionof said bellows structure, annular resilient damping material engaging loops of the folds in said bellows structure and a protectivecasing surrounding and enclosing both said bellows structure and the annular damping material engaged with the folds of the latter.

5.- In combination, a compass or like sensitive instrument and a cushion support for the same, comprising an expansible and contractible resilient bellows structure connected at one end with said instrument, supporting means connected with the opposite end portion of said bellows structure, annular resilient damping material engaging loops of the folds in said bellows structure, a protective casing surrounding and enclosing said bellows structure and damping material and'said damping material being in the form of a cushioning layer interposed between the bellows structure and the surrounding casing and held by said casing in engagement with the outer loops of the folds of the bellows structure.

6. In combination, a compass or like sensitive instrument and a cushion supportior the same, comprising an expansible and contractible resilient bellows structure connected at one end with said instrument, supporting means connected with the opposite end portion of said bellows structure and annular washer-like resilient damping material seated in an outwardly opening fold in said bellows structure.

7. In combination, a compass or like sensitive instrument and a cushion support for the same, comprising an expansible and contractible resilient bellows structure connected at one end with said instrument, supporting means connected with the opposite end portion of said bellows structure and annular washer-like resilient damping material seated in an inwardly opening fold in said bellows structure.

8. In combination, a compass or like instrument and a mounting therefor comprising an expansible and'contractible resilient bellows connected at one end with said instrument, supporting means connected with the Opp site end of said bellows, said bellows, instrument and supporting means being combined to form a displacement chamber with the supported instrument and bellows operating as a movable piston for displacement of air and the chamber thus defined having an air relief opening or openings for regulating the damping effect exerted by the displaced air on the bellows and supported instrument.

9. A compass mounting, comprising in comv bination, a generally cylindrical resilient bellows disposed with the axis of the same substantially vertical and having freely flexing laterally extending folds yieldable in various directions but rigid torsionally, means securing one end of said bellows in supported relation and fixed against rotation, a compass or like sensitive instrument concentrically related to said generally cylindrical bellows and means securing said lnstru-' vertical and having freelyfiexing laterally extending folds yieldable in various directions but rigid torsionally, means securing-one end of said bellows in supported relation and fixed against rotation, acompass or like sensitive instrument concentrically related to said generally cylindrical bellows, means securing said instrument in supv ported relation to the opposite end of the bellows and fixed against rotation in respect thereto and whereby said instrument will be resiliently cushioned in various directions while held rigidly fixed on a definite line and damping means cooperatively related with said bellows to govern the cushioning movements of the same.

11. A compass mounting, comprisinglin combination, a generally cylindrical resilient bellows disposed with the axis of the same substantially vertical and having freely flexing laterally extending folds yieldable in various directions but rigid torsionally, means securing one end of said bellows in supported relation and fixed against rotation, a compass or like sensitive instrument concentrically related to said generally cylindrical bellows, means securing said instrument in supported relation to the opposite end of the bellows and fixed against rotation in respect theretoand whereby said instrument will be resiliently cushioned in various directions while held rigidly fixed on. a definite line, said supported instrument being located within said generally cylindrical bellows and the supporting means for the bellows' including a casing surrounding but spaced from said bellows, said bellows instrument and casing being combined to form a displacement chamber with the supported instrument and bellows operating as a movable piston for displacement of air for damping the vibratory movements.

* LUIS or: FLOREZ. 

